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2019 GMC AT4 w. empty trailer bottoming out!

21STCMC
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21STCMC Enthusiast

21STCMC

Posted
Posted

Brand new 2019 AT4 with 6.2 and 10 speed, hooked up my 24' ATC aluminum trailer before I put my car in it and it bottoms out on the bump stops,

just put my 2945 lb race car in and the truck, now sagging in the back so bad I had to change receptor and ball out just to release the jack on the trailer 

Drove it around the block and it steers like crap due to the suspension being bottomed out

This truck supposedly has 9k plus towing capacity? 

 

My 2015 Suburban w. 5.3 is perfectly level when towing the exact same load

 

Anyone with same towing problems?

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amxguy1970
amxguy1970

This is why people need to vet the information from others carefully because of false information, such as your comments about "Tenneco" Rancho shocks being related to his sag. His truck not holding t

Jack D
Jack D

21STCMC - Your pictures do not show your hitch setup, but you seem to have your trailer just sitting on the ball, with the truck springs taking all of the tongue load. That is an improper setup for th

gothp28
gothp28

If you are using the same hitch you were on your old vehicle that could be the problem as the AT4 is much taller you need to have a larger drop. I have not been towing with mine yet because I need a

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Controller23 Enthusiast

Controller23

Posted
Posted

Sounds like something’s wrong. I put a 4500lb travel trailer on my z71 and it barely moved. What’s the tongue weight of your trailer?


Sent from my iPhone using Tapatalk

gothp28 Enthusiast

gothp28

Posted
Posted

If you are using the same hitch you were on your old vehicle that could be the problem as the AT4 is much taller you need to have a larger drop. I have not been towing with mine yet because I need a new hitch to get it lower to the ground to make the load level.

Sent from my SM-G965U using Tapatalk

  • Like 2
Sierra Dan Senior Enthusiast

Sierra Dan

Posted
Posted
20 hours ago, 21STCMC said:

Brand new 2019 AT4 with 6.2 and 10 speed, hooked up my 24' ATC aluminum trailer before I put my car in it and it bottoms out on the bump stops,

just put my 2945 lb race car in and the truck, now sagging in the back so bad I had to change receptor and ball out just to release the jack on the trailer 

Drove it around the block and it steers like crap due to the suspension being bottomed out

This truck supposedly has 9k plus towing capacity? 

 

My 2015 Suburban w. 5.3 is perfectly level when towing the exact same load

 

Anyone with same towing problems?

Your problem is related to the less than optimum factory Tenneco "Rancho" shocks. 

A shock improvement or airbag setup will help yield better towing results. :thumbs:

21STCMC Enthusiast

21STCMC

Posted
  • Author
Posted

Thanks Dan for the reply, can you suggest a specific model/brand (direct fit) for this application

 

I really appreciate it 

 

Best Regards,

John P

21STCMC Enthusiast

21STCMC

Posted
  • Author
Posted
1 hour ago, gothp28 said:

If you are using the same hitch you were on your old vehicle that could be the problem as the AT4 is much taller you need to have a larger drop. I have not been towing with mine yet because I need a new hitch to get it lower to the ground to make the load level.

Sent from my SM-G965U using Tapatalk
 

Believe it or not my 2015 stock Suburban hitch receptacle sits 2-3" taller than the "lifted" AT4

21STCMC Enthusiast

21STCMC

Posted
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Posted
6 hours ago, Controller23 said:

Sounds like something’s wrong. I put a 4500lb travel trailer on my z71 and it barely moved. What’s the tongue weight of your trailer?


Sent from my iPhone using Tapatalk

You may have the "Max Tow" Package, after further study I see that the AT4 & Denali do not come with and it's not available on either model, forcing someone

that wants to tow into a Sierra with a Max Tow option, hard to believe that is needed for such little weight 

gothp28 Enthusiast

gothp28

Posted
Posted
Believe it or not my 2015 stock Suburban hitch receptacle sits 2-3" taller than the "lifted" AT4
If its 3in lower That would mean the trailers nose would also be 3" lower meaning it has way too much tongue weight.

Sent from my SM-G965U using Tapatalk

  • Like 2
CRApex Enthusiast

CRApex

Posted
Posted (edited)

How bout a set of Timbrens as a cheap fix?  Take about 5 minutes to install.

Edited by CRApex
21STCMC Enthusiast

21STCMC

Posted
  • Author
Posted
2 hours ago, gothp28 said:

If its 3in lower That would mean the trailers nose would also be 3" lower meaning it has way too much tongue weight.

Sent from my SM-G965U using Tapatalk
 

Went from a drop hitch to straight, trailer was same height

Smoothie Enthusiast

Smoothie

Posted
Posted

I don’t believe you can order Z71 with max tow.   I ordered my LTZ and it my was either Max Tow or Z71.   Ordering Max Tow canceled out the Z71 option.

Sierra Dan Senior Enthusiast

Sierra Dan

Posted
Posted

John, 

 

Some on the K2 forum have reported good results with Bilstein 4600 or 5100 shocks when towing.

Sounds like you are pulling a beast. An air bag setup will probably work best with your situation.

Daverado Enthusiast

Daverado

Posted
Posted

Shocks can slow down bottoming out, they are supposed to reduce the bounciness/"shock" of the springs working.  If you are fully bottomed-out and not just bouncing off the bump stops occasionally then you need stronger or taller springs, not different shocks.  If you are just bouncing off the stops then stronger shocks might be enough to slow/stop that.  Shocks don't hold the truck up, springs do.

 

Airbags are spring alternatives not shock alternatives so that sounds like a good choice.

  • Like 2
Racindave Enthusiast

Racindave

Posted
Posted

I wouldn’t think an empty aluminum trailer would bottom out any truck much less a max tow pkg.. something has to be wrong with leaf springs....

MadCaddie Enthusiast

MadCaddie

Posted
Posted

I'm gonna put an airlift kit in my AT4 on mine just because of ride quality and my plans to lift/level but I def don't need it.  

 

It doesn't even squat a little when I put my 18ft flatbed on there and that's got to weigh close to the same as your atc.  I've hauled a 4 place loaded with sleds and gear and it simply leveled the truck out. 

 

Sounds like something else is wrong to me.. 

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